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ABI 103: Midterm 1_Hess
UC Davis
121
Biochemistry
Undergraduate 4
01/21/2019

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Term
Central Dogma
Definition
*important because dysfunction leads to disease
*needed to solve treatments
Term
Nucleotide
Definition
*how DNA carries genetic info in a sequence (DNA = nuc seq)
*4 in DNA/RNA
*COMPOSED: N base, ribose/deoxy, 1+ phosphate
*E carriers(ATP) when release phosphate group
*E storage and transfer to diff molecule

DNA - scribe-> mRNA -lat-> protein
Term
Nitrogenous Base
Definition
PURINE
*adenine, guanine

PYRIMIDINE
*cytosine, uracil/thymine
Term
E use for nucleotides
Definition
*E transferred by phosphates
*humans recycle appropriate ATP/day
*Starch synthesized by adding glucose from repeat ADP gluc
Term
Nucleic Acid Structure
Definition
* 5' --> 3'
(phosphate) --> (hydroxy)

*phosphodiester bonds link nucleotide residues
Term
Chargaff's Rules
Definition
1) DNA has = 3s of A,T / G,C
2) Base composition varies between species
-25-75 mol (bact)
-40 mol (mammals) for G+C
Term
Watson & Crick
Definition
*2, antiparallel polynucleotide strands form DNA helix
*minor/ major groove- uneven width of helix surf
*H bonds cause Chargaff's Rules
Term
Complementary Base Pairing
Definition
*bases of opposite strands interacting by H bond
*3 H bond between G,c
2 between A,T

*break G,C uses more E
Term
DNA & genes
Definition
*DNA contains genetic info in form of genes
*example of transformation of patho/non bacterium
Term
Replication
Definition
*DNA duplication during cell division
*results in identical copies
Term
1 Gene, 1 Enz Theory
Definition
*1 gene scribed/lated to 1 protein
Term
Mutation in nucleotide seq
Definition
* in 3rd position, less immediate effect b/c same AA acid (can be interchanged)
Term
tRNA translation
Definition
*triplet code of RNA has e. AA is based on it
Term
Nucleotide Sequencing
Definition
*ability to determine the nuc seq of a gene/ whole genomes
*gives better understanding of molecular mech that support life
*biotech soln (lrg prod of antimalaria, insulin)
Term
Insulin
Definition
1)DNA from humans put into plasmid (can bemod)
2) recomb DNA loop
3)replicated to make exact copy
4)ferm tank
5) mult copies of human insulin
6) purify and bottle
Term
plasmid
Definition
*allows to insert piece of DNA for replication
*can be mod
Term
Artemisinin
Definition
*antimalria drug
*time consuming found in field plants
*found alt path = more effective
Term
Early Nuc Seq
Definition
*req sm segments of nuc
*76 residues took 7 years

NOW: >3 mil (3Mbp) nuc in hours
Term
Benefit of Nuc Seq
Definition
CATTLE
*painful to dehorn
*introd mutation for cows w/o horns
Term
Types of Nucleotide Sequencing Techniques
Definition
1) FRAGMENTATION OF NUCLEOTIDES USING ENZ
-Gel Electrophoresis

2) CHAIN TERMINATOR
-Sanger

3)AMPLIFICATION OF GENE FRAGMENTS
- PCR
Term
Fragmentation Enz for Nucleotides
Definition
NONSPECIFIC
*breaks phosphodiester between residues
*random choice result in mix of fragments of diff lengths
*EX: snake venom phosphodiesterase

SPECIFIC
*bact enz that recognize and cleave DNA that has a specific nucleotide seq
*cause restriction enz that provide protection against viral infection by destruction of foreign(viral) DNA (b/c not yet methylated)
*2 types: endo/exo nucleases
Term
Exonucleases
Definition
*cleave nucleic acids by removing terminal residues
*recognize seq @end of seq
*last nucletide
Term
Endonucleases
Definition
*cleave nucleic acids w/in nucleotide strand
*recognize seq w/in seq
*cleave at specific recognition sites
* 2 types (Type I, II)
Term
Specific Fragmentation of Nucleotides w/ Enz
Definition
1) introduce into bact
2) viruses attach to wall, inject DNA
3) DNA replicate
4) Restriction enz detect / destroy foreign DNA
5)able to determine self/ foreign
Term
Type I & II Endonucleases
Definition
TYPE I
*recognize DNA in specific spot

TYPE II
*recognize a seq close to the potential modification side
*4-8BP; very useful
*recognize palindrome
Term
Understanding Restriction Endonuc Tables
Definition
↓ : cleavage site
Enz Name: abbreviation of microbe in which enz derived from
R: purine
Y: pyrimidine
Term
Sticky vs Blunt ends
Definition
STICKY
*cuts after 1st nucleotide
*self annealing w/ comp base pairs forms H bonds

BLUNT
*cute random/ or in half
*no true, free nucleotide so cant find complementary BP ad cannot self anneal
Term
Gel Electrophoresis
Definition
*separate DNA frags by size
*order strands by size
*fragments move toward anode b/c - charge
* - charge on DNA phosp cause move toward + (anode)
Term
Sanger Sequencing
Definition
1) DNA template (1 strand)
2) stepwise add of complementary nuc
-add 5-3
3) add primer
-should be complementary to temp
4) dNTPs pair w/ bases
5) incoming nuc joined to polynuc strand in 5-3
6) catalyzed by DNAP1
7) ddNTP bind to terminate
Term
Primer
Definition
*synthesized short fragments of DNA that is complementary to piece want to amplify
*inc H bond breaks = more E needded to separate fragments
Term
DNAP1
Definition
*Extends the primer
*uses the free 3'OH to grow strand
*release pyrophosphate (PPi) w/ e. nuc addn
*connect nuc base to form complementary strand (5'->3')
Term
Components of Sanger
Definition
*DNA template
*DNAP1
*suitable primer
*4 dNTP substrates w/ free nuc residues (for polymerization)
*sm amount of 2,3-ddNTP
*chromophore (flourescent tag, tells end)
Term
ddNTP
Definition
*free hyroxyl group on 3' missing so can't cont chain & sequence stops
*sm amount allows rxn to proceed & terminate 1x to amplify seq
Term
PCR
Definition
*polymerase chain rxn
*amplifies gene fragments
*don't want to interrupt rxn

1) HEAT, separate strands (95C)
2) COOL, primer aneealing
-temp: 5->3 ; primer: 3->5

3)add dNTPs & DNAP extend primer
-DNAP survive repeated heat
4) get 2 copies so repeat (25-30x)

5) RESULT: specific fragment of foreign DNA
6) put into recombinant protein


*need mult copies for experiments
Term
PCR components
Definition
*DNA temp
*primer
*nucleotides
*polymerase
Term
Recombinant Proteins
Definition
*expression of foreign genes using circular DNA
*foreign DNA obtained by PCR, DNA restriction, chem synth

1) take foreign DNA from PCR want to amplify
2)splice plasmid in seq that has same endonuc
2) put back into bact (pUC18, e.coli)
3) sticky ends anneal w/ ligase (foreign temp glued w/ bact DNA)
3) vector w/ new DNA able to replicate
4) ID cells w/ desired DNA (color change)
Term
ID desired cells in Recombinant Proteins
(detecting foreign DNA)
Definition
1) add antibiotics/ chemogenic substances
2) find color change

BLUE: no foreign DNA added
* lacZ encodes for (->) B-galactosidase which cleaves colorless compound X-gal

COLORLESS: foreign DNA
*disrupted LacZ seq and cant -> X-Gal
*resistant to antibiotics
*foreign DNA interrupted the production of B Galactosidase
Term
RNA
Definition
*single stranded = more unstable
*uracil
Term
PCR vs DNA Restriction
Definition
PCR: need to know exact seq to design primer
DNA RESTRICT: use if need mix frags

*differs b/c need to know seq that needs to be ID (only need to know if seq is present in DNA)
Term
Protein
Definition
* primary struct- AA seq liked polypep bonds
*20 AA
*20^n (n= # residues)
Term
Polypeptide
Definition
*100-1000 AA
*EX: Titin- lrgest known protein (34-350AA)
*diversity is unlimited in theory but in a cell limited to size and composition
Term
Polypeptide Diversity
Definition
SIZE
COMPOSITION LIMITATION
POSITION
Term
Size Limitations
Definition
* 40-1000
-in order to fold into right shape for func
-protein synth machinery
Term
Composition Limitations
Definition
*AA occur @ diff freq
*rare AA become a limiting factor
Term
Position Limitations
Definition
*more important than composition
*3D structure is a result of interactions
*Phobic (inside prot), phillic (out, surf) b/c protein in aq soln

EX: Cys
*important b/c 2 Cys residues stabilize protein struct (diS bridge)
Term
Bovine Insulin
Definition
*has Cys diS bridges between 2 dff chains and w/in same chain
*specific on which Cys wants to bind too
Term
Protein Degradation
Definition
*after remove from natural env

CAUSED BY:
1) pH
-need appropriate buffers
2)T
-high T = faster deg
3) presence of protease/nuclease
-protein deg protein
4)absorp to surf
-adhere b/c of air-H2O interface/ glass, plastic
5)storage
-slow oxidation, microbial contamination
Term
Protein Quantification
Definition
ENZ COUPLED ASSAY
*Enz-Linked Immunosorbent Assay (ELISA)

SPECTROPHOTOMETRY
Term
ELISA
Definition
*2 antibodies
1: specific for target prot and linked on solid support
2: bound to assayable enz; specific to 1st antibod

*[protein] measured indirectly by directly measuring enz activity
*good b/c [protein] use to amplify signal
*quantifies enz activity

*confers ability to measure enz activity & tell how much protein present
*measures enz activity
*can determine how much protein in rxn
Term
ELISA Steps
Definition
1) Immobile 1st antibod
2) incubate w/ protein that has sample
2) Add 2nd antibod w/ enz allows to measure
3) Bind, incubation
4) Assay and determine enz activity and convert to initial [protein]

*amount of substrate converted to product indicates amount of assayable protein present
Term
Spectrophotometry
Definition
*uses Lambert-Beer Law
*calc [protein]
*measures enz activity
*read absorbance on machine and calc []
Term
Lambert-Beer Law
Definition
A: what trying to measure
Io: lihgt intensity
E: extinction coeff
c: []
I: light path in cm (light going through)
Term
Absorbance of Polypeptides
Definition
DO ABSORB IN
*UV (200-400nm)
*b/c lrg extinction coeff in the region of aromatic side chains (Phe, Trp, Tyr)

DON'T ABSORB
*Visible light (400-800nm)
*b/c chromophore in visible light region, [] cant be determined
Term
Protein Purification Characteristics & Strategies
Definition
SOLUBILITY
*salt out

IONIC CHARGE
*Ion Exchange Chromatography
*Electrophoresis
*Isoelectric Focusing

POLARITY
*Phobic Interaction Chromatography

SIZE
*Gel Filtration Chromatography
*SDS-PAGE

BINDING SPECIFICITY
*Affinity Chromatography
Term
Salting Out
Definition
*purify based on solubility
*salt added to protein soln (ammonium sulfate)
*proteins have diff behaviors and precipitate based on [salt]
*proteins least solub @ pI

SALT IN:
*solub @ low [ion] increases as salt added
*add salt = inc solub
*proteins remain suspended in soln

SALT OUT:
*as [salt] inc = solub dec
*proteins precipitate of of soln
Term
Milk
Definition
*Microbes in milk grow
*if grow too long, acids synth (lactic, acetic)
*cause pH drop and casein precipitation/ coagulation
*casein forms @ pI (pH2)
Term
Chromatography
Definition
* interaction of proteins w/ mobile/ stationary phase
Term
Ion Exchange
Definition
*total net charge of molecules after separation of ions
*allows to separate molecules easily
*changing buffers pH = manipulation of charge carried by molecule of interest
Term
Isoelectric Point (pI)
Definition
*the pH @ which a molecule has no net charge

pH buff > pI protein
*protein carries -
*+ charged anion exchange resin chosen to capture protein

pH buff < pI protein
*protein carries +
*- cation resin chosen
Term
Protein charge vs pH
Definition
*pH goes above pI = protein has -
-want a anion, +
*protein goes more acidic than pI = cation xΔ
-want a cation, -
Term
Ion Exchange Chromatography
Definition
ANION xΔER
*matrix w/ attached diethylaminoethyl(DEAE)

CATION XΔER
*matrix bearing carboxymethyl(CM) groups

1) mixture w/ 3 proteins
2) stationary matrix has ion xΔer
3) separate based on response to buffer w/ diff [salt] or pH
4) one w/ leat affinity precip out 1st
5) use salt out to dec solub and precipitate out
6) collect eluent in tubes
7) assay [protein]

*separate protein based on attraction ion xΔer but doesn't help find NTerm
*incorporate salt out
Term
Gel (Size Exclusion) Filtration Chromatography
Definition
1) column pacaked w/ large fragments
2) add protein
3) larger protein move faster, sm slower

*small particles have many options to fit through pores, large have less
Term
Affinity Chromatography
Definition
*tells binding specificity characteristics

1) column w/ known matter
2) load w/ something that can bind (ligand , lock and key)
3)protein doesnt bind washed out
4) remove bound protein w/ higher affinity by add compound (must out compete already bound protein)
5) elute

*lock and key analogy
Term
Lock and Key Analogy
Definition
*High selectivity, resolution, capacity
*utilizes proteins biological struct or func
*purifications easily achieved
Term
Polyacrylamide Gel Electrophoresis
(PAGE)
and
SDS-PAGE
Definition
*helps get pure proteins
*size, mass, weight selective
*sim concept to DNA separation
* - -> + (small move faster)
*proteins move in response to electric field
*small move fast so can determine protein
Term
PAGE vs SDS-PAGE
Definition
NO SDS: charge of protein maintained
-proteins migrate toward either electrode
-not suitable for molecular weight determination

*W/ SDS & DENATURIZERS: protein w/ -
-protein full denatured and dissociate from eachother
-overall - due to - on SDS
-protein have rod confirmation instead of tertiary shape

*proteins vary in charge so cant move by self or separate so need to add SDS
*sodium dodecyl sulfate- detergent denaturizes proteins; makes linear and adds overall - to protein
Term
Ultracentrifugation
Definition
1) centrifuge mix and see sep based on mass
2) elute
3) centrifuge powerful so allows to separate
Term
Protein Sequencing Techniques
Definition
END GROUP ANALYSIS
- Dansyl Chloride
- Edman Degradation

CLEAVE DIS BONDS
-mercaptan

CLEAVE POLYPEPTIDE CHAINS
-peptidase
-Mass Spectrometry?

REPEATES REMOVAL OF NTERM AA RESIDUE
-Edman Degredation
Term
Protein Sequencing: End Group Analysis
Definition
*proteins composed of subunits need to be spearated
*protein w/ subunits separate and determine every N term AA -> conclude # subunits
*done by: Dansyl chloride forms yellow compound, edman
*determines only 1st AA in NTerm
Term
Dansyl Chloride
Definition
1)Treatment of dansylated polypep w/ aq acids @ high T
2) have DCl w/ OH and polypep
3) form D polypep (gen N term AA bound to DCl: now flourecent)
4) cleavage peptide bond, all other AA celared and free
- 1 flour AA for e. chain on N term
5) separation of dansylated Nterm residue from other AA through chromatography

*do 1x and chain is fragmented
*removes NTerm and peptide bonds
*need time for rxn to occur
Term
Edman Degradation
Definition
1) PITC (edmans reagent) reacts w/ NTerm Amino group under mild-alkaline condi
2) PTC adduct treated w/ anhydrous trifluoroacetic acid (cleaves Nterm)
3)extract thializonone AA w/ organic solvent
4) treatment w/ aq acid = more stable PTH AA

*rxn allows to remove only N terminal residues 1@ time
*perform repeated discrimination of AA and NTerm
Term
Protein Sequencing: Cleave DiS Bonds
Definition
*ensures peptides linear
*treat w/ 2 mercaptoethanol (breaks all DiS) / other mercaptan
*sep subunits by break DiS

1) free sulfhydryl groups are alkylated w/ iodoacetate (DiS bond between Cys subunits broke)
2)PREVENTS REFORMATION of DiS
Term
Protein Sequencing: Cleave Polypeptide Chains
Definition
*uses peptidases or chem reagents w/o restriction enz
-peptidase more specific , can select specificity
*endopeptidase -> sm protein frags
*endo/exo peptidase have side chain requirements for scissile pep bond
*specific/non used to recognize bond that want cleaved
*Mass Spec

1) Cyanogen bromide reacts w/ Met
2) cleave peptide bond on CTerm
3) New CTerm residue forms cyclic peptidyl homoserine lactone
Term
Scissile Peptide bond
Definition
*bond recognized and cut

Trp: high specificity
-cleaves peptide bonds on CSide of + Arg,Lys if not next to Pro
-allows to cleave specific region in peptide
Pep: nonspecific
Term
Mass Spectrometry
Definition
*get seq based on mass:charge (m/z)
*cleave and run chromatography

1)put protein mix in gas phase
2) vaporize
3) run proteins through vaccuum
4) apply N gas
5)see protein charge depending on Arg, Lys
6)detects mass:charge in proteins
7)differentiate protein based on mass
Term
Protein Sequencing: Repeated Removal of NTerm AA Residue
Definition
*Edman: only NTerm removed
Term
Yogurt components
Definition
*fermented milk
*digested lactose
*specific bact
*nutrients (Ca, P, K, vit B2,B12)
Term
Yogurt History
Definition
*10000-5000BCE milk incorporated in diet b/c anim
*safe for storing other than drying
-discovered b/c kept in intestinal bags and microbes began to ferment
*medical purposes
*need 3 servings/day

Grigorov: lactic acid bact (tang taste), 20th century
Dannon: 1st yogurt lab/ factory
Term
Yogurt and Lactose Intolerance
Definition
*helps introduce Ca, vit D
*bact already digest lactose so person w/o lactase can ingest w/o problem
*Asian, Af Am, Indian have higher intakes of yogurt because more lactose intolerant
Term
Benefits of Yogurt
Definition
1) Enhanced digestability and bioavailability
-beneifts for lactose intolerance
2) addn of probiotics
-benefits gut microflora b/c dec patho
3) FORTIFIED W/ Ca and Vits
-inc Ca intake
-reduced risk of gastrointestinal disease, cardivasc disease, metabolic syndrome, Type2 diabeters, resp disease,
-inc bone, dental health, pregancy
Term
Symbiotic Bact in Yogurt
Definition
Lactobacillus bulgaricus
Streptococcus thermophilus

*sterile env at low T (36C-42C for 48hr)
Term
Making Yogurt
Definition
1) milk lactose used as fermentation substrate
2) lactic acid/ other compound form (smell)
3) decrease in pH -> deveopment of undesirable microorg delayed
4) Ca, P in milk converted to soluble form
5)no Ca; majority of proteins digested by proteolytic enz enhances digestibility and overall bioavailability
Term
Phylogenetic Trees and DNA sequencing
Definition
*can be used to tell relatedness
*primary struct from related species resemble one another
*primary struct tells how conserved a seq is, seq can build into tree

1)detect mutations
2)shows relationships of proteins
-Mb and Hb only have 18% relatedness
-but still have similar tertiary struct
Term
Myoglobin
Definition
*sm molecule (153 resid)
*simple ox binding behavior
*8 a-helices connected by short polypep
*heme group interact w/ polypep
*musc rapidly respires under high exertion (high O2)
-diffusion of O2 from caps to tiss is limited by low solub in aq soln (10^4M blood)
Term
Oxygen Binding Mb and Hb
Definition
*reversible binding of O2 so can be used in necessary places
*AA allow reversible bind

PROB: bind other molecules
*CO, NO, H2S can bind to heme groups on protein
*higher affinity than O2 so very toxic
*CO has 200x greater affinity for Hb than O2

EX: Birds in Mine Shaft
*inc in other gases that bind heme
Term
Mb in aquatic
Definition
*used as O2 storage; [musc Mb] 10x > terrestrial
*needed for diving and long periods under water
Term
Heme
Definition
*bind and release O2
*heterpcyclic ring syst of porphyrin derivate
*in phobic pocket between E & F helix
*4 pyrrole group (A-D) linked by menthene bridge
*has ferrous Fe (FeII) to bind O2
-Fe linked to N on His side chain
*5N total

OXYGENATED Fe(II):
deep purple -> scarlet red (venous vs arterial)

EX: Hb, Mb, CytC
Term
Heme Ligands
Definition
1) Pyrrole A
2) Pyrrole B
3) Pyrrole C
4) Pyrrole D
-all have N
5)His F8
-allows reversibly bind
-binds to Fe
6) O2
-forms interaction with His E7 and Fe
Term
Mb Struct
Definition
*Val E11 and Phe CD1 hold heme in place
-allow and restrict access of O2 to protein
-grab and allow His to grab O2
-side chains swing as protein breathes to allow O2 to enter and exit
-change in conformation allows O2 bind and stay bound
*heme between E & F helices w/ phobic interactions
*His E7: interacts w/ O2 by H bond

HISF8 __ Fe -- O2 -- HISE7
Term
Ferrous Fe Exposed to O2
Definition
BAD
*ferrous Fe of isolated heme is irreversibly oxidized to ferric Fe
-CO molecule bound to heme and color change
-metmyoglobin/methemoglobin formed (brown meat, dried blood)

GOOD
*protein portion of Mb prevents oxidation and allows reversible
*reversible binding: Mb + O2 ⇌ MbO2
Term
O2 Dissociation of Mb
Definition
Yo2: fractional saturation
-the fraction of O2 bind sites occupied by O2
-0 = no O2 bound to Mb
-1 = all bind sites of Mb taken

pO2: partial press of O2
-ox tension
- [O2] torr

K: dissociation Constant
-value of pO2 at which fractional saturation y=.5
-pO2 @ which 1/2 bind sites occupied

p50: [o2] @ .50 of O2 binding sites occupied
-press at which Mb is 50% sat
Term
O2 Binding Curve Mb
Definition
STANDARD BODY COND Mb:
YO2: .5 @1/2 sat
pO2 = 2.8 torr
*Almost full satu in blood Mb
*arterial: 100 torr, venous: 30 torr
p50= 2.8torr
*simple binding = hyperbolic shape

*Mb like to occupy all bind sites so carry from blood -> musc
Term
Mb Function
Definition
1) Facilitates O2 diffusion in musc
-major physio role
-efficiently relays O2 from caps to musc cells
-prob b/c low solub so Mb inc O2 solub in musc

2) Oxygen Storage (aquatic mammals)
-Increases O2 solub in musc cells
-diffusion limited by low solub, Mb inc solub
Term
Hb Difusion
Definition
*small animals rely on diffusion for O2
*lrg animals (>1mm thick) cant satisfy
-have circ syst w/ O2 binding molecule (Hb, hemerythrin, hemocyanin) to boost limited solub of O2 in H2O
-need syst to inc solub in H2O
Term
Hemerythrin & Hemocyanin
Definition
*don't have heme group, only in invertebrate
-'heme' referring to in the blood

HEMERYTHRIN
colorless -> violet,pink b/c O2 states of bind molecule (when oxygenated)

HEMOCYANIN
colorless -> blue when binds to O2
extracellular transport
Term
Hemoglobin
Definition
*delivers O2 to various tiss
*O2 bind explains control of enz act
*tertramer (a2B2) consisting of 2 dimers of aB protomers
Term
O2 Binding in Hb
Definition
1) O2 bind
2) conformational change (protomer rotate 15*)
3) change cause interaction of subunits and AA
-most interactions phobic allows for proper bind
4) shatters deoxyhemoglobin crystals when exposed to Ox
5) B subunits closer together

*associations have extensive contacts, mostly phobic
Term
O2 Binding Behavior of Hb
Definition
*sigmoidal shape
-coop bind, blood delivering/ releasing more O2 to tiss than Mb

*less affinity for O2 than Mb
-Mb is able to pull away O2 molecules from heme (high association w/ O2 (tight)

*increase in slope
-caused by affinity increase after 1st O2 bind
Term
O2 Binding Curve Hb
Definition
STANDARD BODY COND Hb:
YO2: .95 @ full sat of arterial O2 (all bind sites occupied)
pO2 = 100 torr

YO2: .55 @ 1/2 sat of venous O2
pO2: 25 torr

p50= 26 torr
*cooperative binding = sigmoidal shape
Term
Cooperative Binding
Definition
*one encourages bind of another
*as more O2 binds, affinity for next increases
*binding of 1 ligand affects binding of additional ligands to another
*O2 bind to 1 subunit increases O2 binding of remaining
-Hb subunits compete for first O2
Term
Hill Equation
Definition
*describes the degree of sat of Hb (func of pO2)
*describes O2 binding curve of Hb
Term
Hill Constant
Definition
n=1
*noncooperative O2 binding
*bind of O2 is independent (won't have an affect on the other)

n>1
*positively cooperative
*bonding of 1 O2 increases affinity of Hb for further binding

n<1
*negatively cooperative
*O2 binding reduces affinity of Hb for bind other O2
Term
Forms of Hb
Definition
T
*deoxyHb
*unoccupied, no O2 bound
*4 hemes ABOVE heme plane (near His F8)

R
*oxyHb
*Fe(II) moves into center plane

*T->R conformational change when O2 bind
-both states stable
*H bond between AA change depending on T or R
Term
pk and T->R
Definition
T -> R
*pK dec (N term, C term of a/B residues)
*more acidic, more likely to give up protons
*pH drop, inc [H] (shifts affinity for O2)

*Hb release .6 proton for each binding O2
Term
Bohr Effect
Definition
1) Inc pH cause inc in affinity for Hb
-affinity (of O2 for Hb) inc as pH inc ([H] dec)
-vice versa
-allows Hb to release & bind O2 in lung, musc, resp tiss

2) Produced CO2 diffuses slowly from resp tiss to caps; dissolved CO2 slowly forms BiCarb
-important role in o2/CO2 exchange between lung and resp tiss
- LUNG HbO2 affinity < MUSC MbO2 affinity

*provides the mech to provide additional O2 in highly active musc (pO2 <20torr)
Term
Carbonic anhydrase
Definition
*in erythrocytes
*accelerates formation of biCarb
*need act b/c w/o -> inc [Co2] have bubble is blood
-instead seen as BiCarb b/c of H2O
Term
Capillary Hb transport
Definition
pO2 low
*HCO3- formation gen heat
* Hb in T state takes H
*form T stateinduces Hb to release O2
*H+ uptake facilitates CO2 transport by stim HCO3 form
*equil: HbH removes proton from HCO3- +H and allows to push towards lungs
Term
Lung Hb transport
Definition
pO2 HIGH
*T->R triggers release of H (ion pair) so now Hb can take up O2
Term
Lactic Acid
Definition
*normally, no change in blood pH caused by Hb->Hbx exchange
-lactic acid causes pH decrease
*highly act musc generate lac acid
-lac acid -> pH drop -> more O2 released (sm pH = more P2 release)
Term
Carbamates
Definition
*form w/ CO2 so CO2 does not exist as CO2 in blood
*forms at Nterm AA
*THb bind more carbamate CO2 than R
*protons released at formation
-protons promote O2 release (Bohr Effect)

high [Co2] -> favor T state -> release O2
Term
Bisphosphoglycerate
Definition
*protein that affecs the affinity of Hb (decreases affinity)
-pure Hb higher affinity > blood Hb b/c CO2 and other components affect
-allows transfer of maternal, fetal blood


MAMMALS
*decrease Hb affinity by keeping it in deoxy form

VERTS
*other compounds that give same affect
Term
BPG binding
Definition
*binds to deoxyHb and keep in T state to dec O2 affinity
*binds tightly to deoxyHb, weakly to oxyHb

ART: pO2= 100, Hb sat w/ O2= 95%
VEN: pO2= 30, Hb sat w/ O2= 55%

*in caps, Hb unloads 40% bound O2
Term
NO BPG
Definition
*Hb affinity inc -> little bound O2 released
*curve at lower pO2
Term
BPG in fetus
Definition
*helps supply fetus w/ O2 (from maternal circ by placenta)
*[BPG] same in adult, fetal
-adult BPG binds tighter to Hb
-fetal has high BPG affinity, maternal has low
-low BPG affinity (maternal)= high O2 affinity
*b/c fetal has higher O2 affinity, facilitated transfer of O2 to fetus
Term
Fetal Hb
Definition
*subunit composition of a2y2 (adult= a2B2)
*y changes to B
*His residue in B chain form interact w/ BPG; His stabilizes BP-deoxyHb complex

*y has uncharged Ser which allows low affinity in maternal
Term
Carbon Monoxide (CO)
Definition
*colorless/odor/taste, non irritating gas
*leading cause death
*can kill fast or slow (35ppm for 8hr w/o effects)
Term
Causes of CO Poisoning
Definition
*inhaling combustible fumes
-generators, lanterns, gas ranges, etc
*inhaling smoke from closed place fire
Term
How CO works
Definition
*causes hypoxia at tiss level
*CO binds to heme -> O2 cant bind (200x > affinity) -> form carboxyHb (COHb) -> less O2 carried
*when binds to cardiac Mb, less O2 available for aerobic metab -> dec cardiac contract, less O2 transport (AKA low flow hypoxia)
Term
CO Poisoning Effects
Definition
*every body syst (heart, brain, lung sens)
*causes headache, nausea, vomit, fatigue
*cause low flow hypoxia
*poisoning worse when w/ other cond
*blood, O2 content redby 1/2 w/ COHb
Term
Treatment for CO Poison
Definition
*ID symptoms
*COHb levels:
-danger if > 25% COHb
-lethal if > 50% COHb
*measure ven,art blood gases
-pO2 levels
*complete blood count assess
*lactate levels
*cardiac enz levels

*admin O2 @ 15L/min (4hr)
-red 1/2 life COHb (300-90min)
*severe cases:
-intubate -> ICU, monitor heart -> cardiovasc resp support -> meurologic development -> HBO therapy (heart chamber oxygenation) = red 1/2 life COHb (300-30min)
Term
Prevention of CO Poison
Definition
*CO detector
*professionally installed fuel burning appliance
*vented space heaters
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